Enable hiding/showing top controls persistently

Pass down to the renderer whether or not we should allow showing the fullscreen controls
as well as hiding.

BUG=161303


Review URL: https://chromiumcodereview.appspot.com/12954003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@191210 0039d316-1c4b-4281-b951-d872f2087c98

4 files changed, 46 insertions, 14 deletions

diff --git a/cc/input/top_controls_manager.cc b/cc/input/top_controls_manager.cc
index e1698f1..343dd3c 100644
--- a/cc/input/top_controls_manager.cc
+++ b/cc/input/top_controls_manager.cc
@@ -40,7 +40,7 @@ TopControlsManager::TopControlsManager(TopControlsManagerClient* client,
                                        float top_controls_hide_threshold)
     : client_(client),
       animation_direction_(NO_ANIMATION),
-      enable_hiding_(true),
+      visibility_restriction_(NONE),
       controls_top_offset_(0.f),
       top_controls_height_(top_controls_height),
       current_scroll_delta_(0.f),
@@ -55,15 +55,30 @@ TopControlsManager::TopControlsManager(TopControlsManagerClient* client,
 TopControlsManager::~TopControlsManager() {
 }
 
-void TopControlsManager::EnableHidingTopControls(bool enable) {
-  enable_hiding_ = enable;
+void TopControlsManager::UpdateTopControlsState(bool enable_hiding,
+                                                bool enable_showing,
+                                                bool animate) {
+  float final_controls_position = 0.f;
+
+  if (enable_hiding && enable_showing) {
+    visibility_restriction_ = NONE;
+  } else if (enable_showing || !enable_hiding) {
+    visibility_restriction_ = ALWAYS_SHOWN;
+  } else {
+    visibility_restriction_ = ALWAYS_HIDDEN;
+    final_controls_position = -top_controls_height_;
+  }
 
-  if (!enable) {
+  if (visibility_restriction_ != NONE &&
+      final_controls_position != controls_top_offset_) {
     ResetAnimations();
-    if (controls_top_offset_ != 0) {
-      SetupAnimation(SHOWING_CONTROLS);
-      client_->setNeedsRedraw();
+    if (animate) {
+      SetupAnimation(visibility_restriction_ == ALWAYS_SHOWN ?
+          SHOWING_CONTROLS : HIDING_CONTROLS);
+    } else {
+      controls_top_offset_ = final_controls_position;
     }
+    client_->setNeedsRedraw();
   }
 }
 
@@ -75,7 +90,9 @@ void TopControlsManager::ScrollBegin() {
 
 gfx::Vector2dF TopControlsManager::ScrollBy(
     const gfx::Vector2dF pending_delta) {
-  if (!enable_hiding_ && pending_delta.y() > 0)
+  if (visibility_restriction_ == ALWAYS_SHOWN && pending_delta.y() > 0)
+    return pending_delta;
+  else if (visibility_restriction_ == ALWAYS_HIDDEN && pending_delta.y() < 0)
     return pending_delta;
 
   current_scroll_delta_ += pending_delta.y();
diff --git a/cc/input/top_controls_manager.h b/cc/input/top_controls_manager.h
index 59289f6..78ccf80 100644
--- a/cc/input/top_controls_manager.h
+++ b/cc/input/top_controls_manager.h
@@ -31,6 +31,12 @@ class CC_EXPORT TopControlsManager
     HIDING_CONTROLS
   };
 
+  enum VisibilityRestriction {
+    ALWAYS_SHOWN,
+    ALWAYS_HIDDEN,
+    NONE
+  };
+
   static scoped_ptr<TopControlsManager> Create(
       TopControlsManagerClient* client,
       float top_controls_height,
@@ -47,7 +53,9 @@ class CC_EXPORT TopControlsManager
   }
   AnimationDirection animation_direction() { return animation_direction_; }
 
-  void EnableHidingTopControls(bool enable);
+  void UpdateTopControlsState(bool enable_hiding,
+                              bool enable_showing,
+                              bool animate);
 
   void ScrollBegin();
   gfx::Vector2dF ScrollBy(const gfx::Vector2dF pending_delta);
@@ -73,7 +81,7 @@ class CC_EXPORT TopControlsManager
 
   scoped_ptr<KeyframedFloatAnimationCurve> top_controls_animation_;
   AnimationDirection animation_direction_;
-  bool enable_hiding_;
+  VisibilityRestriction visibility_restriction_;
   float controls_top_offset_;
   float top_controls_height_;
 
diff --git a/cc/trees/layer_tree_host.cc b/cc/trees/layer_tree_host.cc
index 75b6118..c98c81b 100644
--- a/cc/trees/layer_tree_host.cc
+++ b/cc/trees/layer_tree_host.cc
@@ -983,13 +983,18 @@ void LayerTreeHost::SetDeviceScaleFactor(float device_scale_factor) {
   SetNeedsCommit();
 }
 
-void LayerTreeHost::EnableHidingTopControls(bool enable) {
+void LayerTreeHost::UpdateTopControlsState(bool enable_hiding,
+                                           bool enable_showing,
+                                           bool animate) {
   if (!settings_.calculate_top_controls_position)
     return;
 
   proxy_->ImplThread()->PostTask(
-      base::Bind(&TopControlsManager::EnableHidingTopControls,
-                 top_controls_manager_weak_ptr_, enable));
+      base::Bind(&TopControlsManager::UpdateTopControlsState,
+                 top_controls_manager_weak_ptr_,
+                 enable_hiding,
+                 enable_showing,
+                 animate));
 }
 
 bool LayerTreeHost::BlocksPendingCommit() const {
diff --git a/cc/trees/layer_tree_host.h b/cc/trees/layer_tree_host.h
index 220cbb5..b412dab 100644
--- a/cc/trees/layer_tree_host.h
+++ b/cc/trees/layer_tree_host.h
@@ -224,7 +224,9 @@ class CC_EXPORT LayerTreeHost : NON_EXPORTED_BASE(public RateLimiterClient) {
   void SetDeviceScaleFactor(float device_scale_factor);
   float device_scale_factor() const { return device_scale_factor_; }
 
-  void EnableHidingTopControls(bool enable);
+  void UpdateTopControlsState(bool enable_hiding,
+                              bool enable_showing,
+                              bool animate);
 
   HeadsUpDisplayLayer* hud_layer() const { return hud_layer_.get(); }